The present invention relates to a nuclear power plant construction method, and more particularly to a method of joining a reactor building (RB) to a reinforced concrete containment vessel (RCCV) as a contiguous portion therebetween.
In a general method of constructing a reactor building, an RCCV having a cylindrical outer wall is installed immediately after forming a concrete foundation base mat of the reactor building. The reason why the cylindrical wall is completed preferentially is that the construction of the RCCV constitutes critical pathes in the whole constructing working of the reactor building.
Other constructing workings are successively done, after the construction of the cylindrical wall of the RCCV, by mainly casting each floor slab, an RB outer side wall, a supporting pedestal of a reactor pressure vessel, an RCCV top slab, an RB slab and an RB roof truss in this order.
Then, the joining of the reactor building to the RCCV as contiguous portion work therebetween is carried out by casting concretes in spaces between the slabs, i.e. RB slabs and the floor slabs, of the reactor building and the outer surface of the cylindrical wall of the RCCV.
Now, before the casting, reinforcing members are embedded in one ends into the concrete bodies of the RB slabs and the wall of the RCCV so as to extend outward therefrom at the other ends. Thereafter, some other reinforcing members as re-bars are placed between the aforementioned reinforcing members and casting frames are then set as curing concrete.
It is however complicated to make the reinforcing members jut out from the concrete body, to temporarily set scaffoldings for this working, to place the other reinforcing members and to set the temporary frames for every floor in the reactor building. In addition, the casting and seting workings of the concrete also make complicated the whole construction workings as well as the disassembling of the scaffoldings and the temporary frame. These complicated workings make delay the completion of the construction of the final reactor building and compel workers to work hard in the working places.
In the working places, many equipments and machineries for the nuclear power plant are arranged on the respective floors, i.e. RB slabs, of a reactor building, and these equipments and machineries are, in the actual arrangement, carried in the reactor building by hanging them by a crane, for example, from the upper side of the reactor building and set to the predetermined positions on the respective floors. However, because the floor portions of the joining portions between the reactor building and the RCCV are constructed after the installation of the reactor building and the respective floors and, moreover, the reinforcing members project from the RB slabs and the wall portions of the RCCV, the equipments and machineries to be arranged to these floor portions of the joining portions (contiguous portion) must be carried in the reactor building through openings formed temporarily to the side wall of the reactor building after the construction of the reactor building. These openings also must be closed after the conveyance of these equipments and machineries
As described above, in the conventional method of constructing a reactor building, it is necessary to provide the reinforcing members having ends embedded in the RB slabs and the outer wall of the RCCV for the joining portions therebetween, thus being complicated in the actual construction working and troublesome. Moreover, in case of the construction of the joining portions, many additional workings such as assembling and disassembling the working scaffoldings, forming the casting frames and so on, resulting in the elongation of the total working times as well as the increasing of the working steps.
In addition, the conveyance of the equipments and machineries through the openings formed to the side walls of the reactor building after the construction thereof also makes complicated the construction working, which may cause a problem of safety working as well as the elongation of the construction term.